<template>
  <view class="uni-numbox">
    <!-- 		<view @click="_calcValue('minus')" class="uni-numbox__minus uni-numbox-btns" :style="{background}"> -->
    <view @click="_calcValue('minus')" class="uni-numbox__minus uni-numbox-btns">
      <text class="uni-numbox--text" :class="{ 'uni-numbox--disabled': inputValue <= min || disabled }"
        :style="{color}">-</text>
    </view>
    
    <input :disabled="disabled"  @focus="_onFocus"  @blur="_onBlur" class="uni-numbox__value"
      :type="step<1?'digit':'number'" v-model="inputValue" :style="{background, color, width:widthWithPx}" />
    <!-- 		<view @click="_calcValue('plus')" class="uni-numbox__plus uni-numbox-btns" :style="{background}"> -->
    <view @click="_calcValue('plus')" class="uni-numbox__plus uni-numbox-btns">
      <text class="uni-numbox--text" :class="{ 'uni-numbox--disabled': inputValue >= max || disabled || disabledPlus }"
        :style="{color}">+</text>
    </view>
  </view>
</template>
<script>
  /**
   * NumberBox 数字输入框
   * @description 带加减按钮的数字输入框
   * @tutorial https://ext.dcloud.net.cn/plugin?id=31
   * @property {Number} value 输入框当前值
   * @property {Number} min 最小值
   * @property {Number} max 最大值
   * @property {Number} step 每次点击改变的间隔大小
   * @property {String} background 背景色
   * @property {String} color 字体颜色（前景色）
   * @property {Number} width 输入框宽度(单位:px)
   * @property {Boolean} disabled = [true|false] 是否为禁用状态
   * @event {Function} change 输入框值改变时触发的事件，参数为输入框当前的 value
   * @event {Function} focus 输入框聚焦时触发的事件，参数为 event 对象
   * @event {Function} blur 输入框失焦时触发的事件，参数为 event 对象
   */

  export default {
    name: "UniNumberBox",
    emits: ['change', 'input', 'update:modelValue', 'blur', 'focus'],
    props: {
      value: {
        type: [Number, String],
        default: 1
      },
      modelValue: {
        type: [Number, String],
        default: 1
      },
      min: {
        type: Number,
        default: 0
      },
      max: {
        type: Number,
        default: 100
      },
      step: {
        type: Number,
        default: 1
      },
      background: {
        type: String,
        // default: '#f5f5f5'
        default: '#ffffff'
      },
      color: {
        type: String,
        default: '#333'
      },
      disabled: {
        type: Boolean,
        default: false
      },
      disabledPlus: {
        type: Boolean,
        default: false
      },
      width: {
        type: Number,
        default: 30,
      }
    },
    data() {
      return {
        inputValue: 0
      };
    },
    watch: {
      value(val) {
        this.inputValue = +val;
      },
      modelValue(val) {
        this.inputValue = +val;
      }
    },
    computed: {
      widthWithPx() {
        return this.width + 'px';
      }
    },
    created() {
      if (this.value === 1) {
        this.inputValue = +this.modelValue;
      }
      if (this.modelValue === 1) {
        this.inputValue = +this.value;
      }
    },
    methods: {
      _calcValue(type) {
        if (this.disabled || (type === "plus" && this.disabledPlus)) {
          return;
        }
        const scale = this._getDecimalScale();
        let value = this.inputValue * scale;
        let step = this.step * scale;
        if (type === "minus") {
          value -= step;
          if (value < (this.min * scale)) {
            return;
          }
          if (value > (this.max * scale)) {
            value = this.max * scale
          }
        }

        if (type === "plus") {
          value += step;
          if (value > (this.max * scale)) {
            return;
          }
          if (value < (this.min * scale)) {
            value = this.min * scale
          }
        }

        this.inputValue = (value / scale).toFixed(String(scale).length - 1);
        // TODO vue2 兼容
        this.$emit("input", +this.inputValue);
        // TODO vue3 兼容
        this.$emit("update:modelValue", +this.inputValue);
        this.$emit("change", +this.inputValue);
      },
      _getDecimalScale() {

        let scale = 1;
        // 浮点型
        if (~~this.step !== this.step) {
          scale = Math.pow(10, String(this.step).split(".")[1].length);
        }
        return scale;
      },
      _onBlur(event) {
        this.$emit('blur', event)
        let value = event.detail.value;
        if (isNaN(value)) {
          this.inputValue = this.value;
          return;
        }
        value = +value;
        if (value > this.max) {
          value = this.max;
        } else if (value < this.min) {
          value = this.min;
        }
        const scale = this._getDecimalScale();
        this.inputValue = value.toFixed(String(scale).length - 1);
        this.$emit("input", +this.inputValue);
        this.$emit("update:modelValue", +this.inputValue);
        this.$emit("change", +this.inputValue);
      },
      _onFocus(event) {
        this.$emit('focus', event)
      }
    }
  };
</script>
<style lang="scss">
  $box-height: 25px;
  $bg: #f5f5f5;
  $bg2: #ffffff;
  $br: 30px;
  $color: #333;

  .uni-numbox {
    /* #ifndef APP-NVUE */
    display: flex;
    /* #endif */
    flex-direction: row;
  }

  .uni-numbox-btns {
    /* #ifndef APP-NVUE */
    display: flex;
    /* #endif */
    flex-direction: row;
    align-items: center;
    justify-content: center;
    padding: 0 7px;
    // height: 30px;
    // width: 30px;
    background-color: $bg2;
    /* #ifdef H5 */
    cursor: pointer;
    /* #endif */
    box-sizing: border-box;
  }

  .uni-numbox__value {
    margin: 0 2px;
    background-color: $bg2;
    width: 40px;
    height: $box-height;
    text-align: center;
    font-size: 14px;
    border-width: 0;
    color: $color;
  }

  .uni-numbox__minus {
    border-radius: $br;
    border: 2px solid #FFB200;

    // border-top-left-radius: $br;
    // border-bottom-left-radius: $br;
  }

  .uni-numbox__plus {
    border-radius: $br;
    background-color: #FFD804;
    // border-top-right-radius: $br;
    // border-bottom-right-radius: $br;
  }

  .uni-numbox--text {
    // fix nvue
    line-height: 23px;
    // margin-bottom: 2px;
    padding-bottom: 2px;
    font-size: 22px;
    font-weight: 400;
    color: $color;
    box-sizing: border-box;
  }

  .uni-numbox .uni-numbox--disabled {
    color: #c0c0c0 !important;
    /* #ifdef H5 */
    cursor: not-allowed;
    /* #endif */
  }
</style>